lol thought the key to being a Diaz bro was to smoke loads of crazy shit and have wild rants about life?

VO2 max isnt always a good indicator of performance. For me the best way to conserve your energy is to have efficient, excellent technique, don't spend too long working on endurance and then reducing your productivity at your training sessions through fatigue.

If you actually do need to improve your engine do short sharp sessions a little and often, use bang for your buck type sessions like tabatas or negative work to rest sessions which should improve your general endurance and work capacity. Or drilling at high intensity for longer periods of time to work technique and aerobic endurance.

i find rowing sprints are very effective for getting fight fit!, also, make sure you dont neglect your drills in the club as they are your bread and butter!.....maybe a circuit of high intensity drills, followed by recovery, then look at something like rowing sprints to compliment your base.